The present invention relates to a vehicle suspension apparatus wherein suspension units are held in a soft state during normal driving and are automatically switched to a hard state during high-speed driving, thereby improving driving stability.
In a conventional vehicle suspension apparatus of this type, the velocity detected by a vehicle velocity sensor is compared with a preset switching velocity. When the detected velocity is lower than the switching velocity, the suspension units are held in the soft state. When the detected velocity is equal to or larger than the switching velocity, the suspension units are held in the hard state.
However, when the vehicle is affected by cross winds during travel or when it travels along a rough road, the suspension units are preferably held in the hard state to provide better driving stability even if the actual vehicle velocity is lower than the switching velocity. In the case when a cross wind is light or a road surface is smooth, factors affecting driving stability decrease and even if the vehicle travels at a velocity higher than the switching velocity, the vehicle is preferably held in the soft state to improve riding comfort.